What you saw --- what I posted --- was an AESA board dated around 2007. If it has Altera FPGA dated 2007, then it is something the Chinese would have exceeded long ago. FPGA is also used for prototyping purposes; it does not necessarily mean it will be the chip used on the final product. On the contrary, using FPGA not only is more expensive, but produces more heat and can be slower than hardwired mass manufactured for that purpose ASIC. If you are making prototype radars, using FPGA is fine, but once the radar goes into mass manufacture, each array can have thousands of elements, and at this point, it would make sense to go to ASIC instead.
ICs used in radars and military applications are not necessarily using the smallest nanometer available. On the contrary, trying to use the smallest process possible makes those smallest transistors more vulnerable to interference, cosmic rays and EMP. In fact, when it comes to space applications, satellites and probes, the chips used are those from old processes with the larger transistor size. It is a good idea to keep obsolete semiconductor processes to produce chips for military and space programs.
As a reminder, power ICs do not require or use the smallest nanometer processes. As power circuits, its the opposite. This includes the all important amplifiers.
I saw one of RT documentaries that are showing a special laboratory making modules for radars, and it was a careful hand made process using generics.
You can see the Altera FPGA on the 2007 board, but the phase shifter and the amplifier are all custom made.
In later years, the design has radically changed.
